HOUSTON (CNNMoney.com) -- The oil is out there. The hard part is getting it to consumers.

Oil industry executives and experts are gathering here this week for the Cambridge Energy Research Associates' annual conference, one of the sector's most impressive showings of energy industry clout outside of an OPEC meeting.

The backdrop: Tight supplies and rising demand for crude. As a result, executives said, the industry faces serious challenges getting oil to market.

The consensus among participants at the conference is that the world has enough oil to meet growing demand, but that the industry must focus more attention on harvesting the oil.

"An oil crisis is coming, and sooner than most people think," said John Hess, chief executive of Hess Corp (HES, Fortune 500)., the integrated oil and gas company with 2006 sales of $29 billion. "All oil producers are not investing enough today."

Rising income of consumers has propped up demand even as crude prices have spiked five fold in the past six years. Hess offered some perspective: On a unit-to-unit basis, oil is still about 10 times cheaper than a Starbucks latte.

Runaway growth in oil use in India and China - the two countries are expected to boast a combined 1.2 billion vehicles by 2050, up from 20 million a few years ago - is expected to push demand above supply sometime between 2015 and 2020, Hess said.

"It's not a matter of endowment, it's a matter of investment," he said.

A small but growing number of analysts disagree with Hess' assertion that there is enough oil in the ground. They say production of oil has peaked or will peak soon, followed by a slow but steady period of decline that could cause major social unrest.

Oil executives, while acknowledging that crude deposits are ultimately limited, said that new technologies should keep crude production rising for at least several decades.

"Many perceive the supply challenge as one of scarcity," said Mark Albers, a senior vice president at Exxon Mobil (XOM, Fortune 500). "There is no question oil is a finite resource, but it's far from finished."

Albers pointed to a U.S. government survey saying the world has three trillion barrels of oil left - compared to the one trillion used so far in history.

There's plenty of oil, it's just hard to reach. But much of what remains lies in remote places, Albers noted. He said producers have to work closely with countries that hold a significant chunk of the remaining supplies.

One of those countries, of course, is Saudi Arabia. The head of the Saudi state oil company said his firm is making the necessary investments to increase oil production to 12 million barrels a day by 2009, up from between 9 million and 10 million barrels a day currently.

"The planet is sufficiently endowed with petroleum resources for decades to come," said Abdallah Jum'ah, chief executive of the Saudi Arabian National Oil Company, which pumps about 4 or 5 times the amount of oil as Exxon. "But if the prevailing confusion over energy policy continues, there is considerable risk the expansion of resources will be compromised."

Jum'ah didn't specify which policies he was referring to, but cautioned against putting too much faith in alternative energy.

"There are expectations for an unrealistic development rate for such resources," he said. "The world cannot afford to leave massive quantities of oil in the ground and move to uncertain technologies."

Renewable energy to the rescue? The U.S. government says that, under current policies, renewable energy will only meet 2 to 5 percent of the country's total energy needs by 2030.

But supporters of renewable energy say it could be much higher by then - up to 50 percent - given the right incentives.

Jum'ah said that global warming "demands our most serious attention," but he added that "we cannot afford to abandon fossil fuels." Oil, he said, helps drive economic growth and lifts people out of poverty.

The climate change debate. Other executives were more forceful in pushing the industry to address the climate change challenge.

"The energy industry should be part of the solution, we have the best understanding of the supply chain," said James Mulva, chief executive of ConocoPhillips (COP, Fortune 500), the third largest oil company in the U.S. behind Exxon and Chevron.

If the industry doesn't engage, Mulva said, "we'll lose the option of influencing policy, and our interests could be marginalized."

Mulva chastised the U.S. government for not taking a more active role in dealing with greenhouse gasses. "The U.S. has missed opportunities to show leadership," he said. The United States, unlike those of most other industrialized nations, failed to ratify the Kyoto treaty, the 1997 agreement mandating a reduction in greenhouse gasses.

Nobuo Tanaka, executive director of the International Energy Agency, said a mandatory target to reduce greenhouse gasses may not solve the global warming problem.

Tanaka outlined a plan calling for massive reductions in carbon dioxide emissions from power plants, a big jump in energy efficiency, and a revamping of the vehicle fleet - along with big investments in conventional energy infrastructure.

The plan would be costly - $50 trillion by 2050 - but he said that price tag represents only 1% of the world's projected economic output over that time.

And the investment would cause a reduction in greenhouse gas emissions by at least 50 percent by 2050 - and avoid the most serious effects of global warming such as widespread flooding and drought.

"The primary scarcity facing the planet is not resources, it's not money," said Tanaka. "It's time."